IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[parseJSON]') AND type in (N'FN', N'IF', N'TF', N'FS', N'FT'))
DROP FUNCTION [dbo].[parseJSON]
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
/*
******************************************************************************************
Purpose:   
Author:     
Date:       

Note:

Modified history
-----------------
Date			Modifier		Task			Remark
----------		---------		-----------		---------------------------------

20220308    PD  负数与bigint/dec(18,6)/dec(26,12) 解析
20220307    PD  不转义 保留原始数据
20220304    PD    @token 200->MAX
20170316    PD    add 排除null
desc
******************************************************************************************
*/

CREATE FUNCTION dbo.[parseJSON](@JSON NVARCHAR(MAX))
RETURNS @hierarchy TABLE
(
element_id INT IDENTITY(1, 1) NOT NULL, /* internal surrogate primary key gives the order of parsing and the list order */
sequenceNo [int] NULL, /* the place in the sequence for the element */
parent_ID INT,/* if the element has a parent then it is in this column. The document is the ultimate parent, so you can get the structure from recursing from the document */
[Object_ID] INT,/* each list or object has an object id. This ties all elements to a parent. Lists are treated as objects here */
NAME NVARCHAR(2000),/* the name of the object */
StringValue NVARCHAR(MAX) NOT NULL,/*the string representation of the value of the element. */
ValueType VARCHAR(10) NOT null /* the declared type of the value represented as a string in StringValue*/
)
AS
BEGIN
    DECLARE
        @FirstObject INT, --the index of the first open bracket found in the JSON string
        @OpenDelimiter INT,--the index of the next open bracket found in the JSON string
        @NextOpenDelimiter INT,--the index of subsequent open bracket found in the JSON string
        @NextCloseDelimiter INT,--the index of subsequent close bracket found in the JSON string
        @Type NVARCHAR(10),--whether it denotes an object or an array
        @NextCloseDelimiterChar CHAR(1),--either a '}' or a ']'
        @Contents NVARCHAR(MAX), --the unparsed contents of the bracketed expression
        @Start INT, --index of the start of the token that you are parsing
        @end INT,--index of the end of the token that you are parsing
        @param INT,--the parameter at the end of the next Object/Array token
        @EndOfName INT,--the index of the start of the parameter at end of Object/Array token
        @token NVARCHAR(MAX),--either a string or object 20220304 200->MAX
        @value NVARCHAR(MAX), -- the value as a string
        @SequenceNo int, -- the sequence number within a list
        @name NVARCHAR(200), --the name as a string
        @parent_ID INT,--the next parent ID to allocate
        @lenJSON INT,--the current length of the JSON String
        @characters NCHAR(36),--used to convert hex to decimal
        @result BIGINT,--the value of the hex symbol being parsed
        @index SMALLINT,--used for parsing the hex value
        @Escape INT --the index of the next escape character

        ,@ValueType varchar(10)=''
	    
	    --20170316 add isnull
	    select @JSON=isnull(@JSON,'')
	    
	  DECLARE @Strings TABLE /* in this temporary table we keep all strings, even the names of the elements, since they are 'escaped' in a different way, and may contain, unescaped, brackets denoting objects or lists. These are replaced in the JSON string by tokens representing the string */
	    (
	     String_ID INT IDENTITY(1, 1),
	     StringValue NVARCHAR(MAX)
	    )
	  SELECT--initialise the characters to convert hex to ascii
	    @characters='0123456789abcdefghijklmnopqrstuvwxyz',
	    @SequenceNo=0, --set the sequence no. to something sensible.
	  /* firstly we process all strings. This is done because [{} and ] aren't escaped in strings, which complicates an iterative parse. */
	    @parent_ID=0;
	  WHILE 1=1 --forever until there is nothing more to do
	    BEGIN
	      SELECT
	        @start=PATINDEX('%[^a-zA-Z]["]%', @json collate SQL_Latin1_General_CP850_Bin);--next delimited string
	      IF @start=0 BREAK --no more so drop through the WHILE loop
	      IF SUBSTRING(@json, @start+1, 1)='"' 
	        BEGIN --Delimited Name
	          SET @start=@Start+1;
	          SET @end=PATINDEX('%[^\]["]%', RIGHT(@json, LEN(@json+'|')-@start) collate SQL_Latin1_General_CP850_Bin);
	        END
	      IF @end=0 --no end delimiter to last string
	        BREAK --no more
	      SELECT @token=SUBSTRING(@json, @start+1, @end-1)
	      --now put in the escaped control characters

          --20220307 不转义 保留原始数据
	      --SELECT @token=REPLACE(@token, FROMString, TOString)
	      --FROM
	      --  (SELECT
	      --    '\"' AS FromString, '"' AS ToString
	      --   UNION ALL SELECT '\\', '\'
	      --   UNION ALL SELECT '\/', '/'
	      --   UNION ALL SELECT '\b', CHAR(08)
	      --   UNION ALL SELECT '\f', CHAR(12)
	      --   UNION ALL SELECT '\n', CHAR(10)
	      --   UNION ALL SELECT '\r', CHAR(13)
	      --   UNION ALL SELECT '\t', CHAR(09)
	      --  ) substitutions

	      SELECT @result=0, @escape=1
	  --Begin to take out any hex escape codes
	      WHILE @escape>0
	        BEGIN
	          SELECT @index=0,
	          --find the next hex escape sequence
	          @escape=PATINDEX('%\x[0-9a-f][0-9a-f][0-9a-f][0-9a-f]%', @token collate SQL_Latin1_General_CP850_Bin)
	          IF @escape>0 --if there is one
	            BEGIN
	              WHILE @index<4 --there are always four digits to a \x sequence   
	                BEGIN
	                  SELECT --determine its value
	                    @result=@result+POWER(16, @index)
	                    *(CHARINDEX(SUBSTRING(@token, @escape+2+3-@index, 1),
	                                @characters)-1), @index=@index+1 ;
	         
	                END
	                -- and replace the hex sequence by its unicode value
	              SELECT @token=STUFF(@token, @escape, 6, NCHAR(@result))
	            END
	        END
	      --now store the string away 
	      INSERT INTO @Strings (StringValue) SELECT @token
	      -- and replace the string with a token
	      SELECT @JSON=STUFF(@json, @start, @end+1,
	                    '@string'+CONVERT(NVARCHAR(5), @@identity))
	    END
	  -- all strings are now removed. Now we find the first leaf.  
	  WHILE 1=1  --forever until there is nothing more to do
	  BEGIN
	 
	  SELECT @parent_ID=@parent_ID+1
	  --find the first object or list by looking for the open bracket
	  SELECT @FirstObject=PATINDEX('%[{[[]%', @json collate SQL_Latin1_General_CP850_Bin)--object or array
	  IF @FirstObject = 0 BREAK
	  IF (SUBSTRING(@json, @FirstObject, 1)='{') 
	    SELECT @NextCloseDelimiterChar='}', @type='object'
	  ELSE 
	    SELECT @NextCloseDelimiterChar=']', @type='array'
	    

      
	  SELECT @OpenDelimiter=@firstObject
	  WHILE 1=1 --find the innermost object or list...
	    BEGIN
	      SELECT
	        @lenJSON=LEN(@JSON+'|')-1
	  --find the matching close-delimiter proceeding after the open-delimiter
	      SELECT
	        @NextCloseDelimiter=CHARINDEX(@NextCloseDelimiterChar, @json,
	                                      @OpenDelimiter+1)
	  --is there an intervening open-delimiter of either type
	      SELECT @NextOpenDelimiter=PATINDEX('%[{[[]%',
	             RIGHT(@json, @lenJSON-@OpenDelimiter)collate SQL_Latin1_General_CP850_Bin)--object
	      IF @NextOpenDelimiter=0 
	        BREAK
	      SELECT @NextOpenDelimiter=@NextOpenDelimiter+@OpenDelimiter
	      IF @NextCloseDelimiter<@NextOpenDelimiter 
	        BREAK
	      IF SUBSTRING(@json, @NextOpenDelimiter, 1)='{' 
	        SELECT @NextCloseDelimiterChar='}', @type='object'
	      ELSE 
	        SELECT @NextCloseDelimiterChar=']', @type='array'
	      SELECT @OpenDelimiter=@NextOpenDelimiter
	    END
	  ---and parse out the list or name/value pairs
	  SELECT
	    @contents=SUBSTRING(@json, @OpenDelimiter+1,
	                        @NextCloseDelimiter-@OpenDelimiter-1)
	  SELECT
	    @JSON=STUFF(@json, @OpenDelimiter,
	                @NextCloseDelimiter-@OpenDelimiter+1,
	                '@'+@type+CONVERT(NVARCHAR(5), @parent_ID))
	  WHILE (PATINDEX('%[A-Za-z0-9@+.e]%', @contents collate SQL_Latin1_General_CP850_Bin))<>0 
	    BEGIN
	      IF @Type='Object' --it will be a 0-n list containing a string followed by a string, number,boolean, or null
            BEGIN
	          SELECT
	            @SequenceNo=0,@end=CHARINDEX(':', ' '+@contents)--if there is anything, it will be a string-based name.
	          SELECT  @start=PATINDEX('%[^A-Za-z@][@]%', ' '+@contents collate SQL_Latin1_General_CP850_Bin)--AAAAAAAA
	          SELECT @token=SUBSTRING(' '+@contents, @start+1, @End-@Start-1),
	            @endofname=PATINDEX('%[0-9]%', @token collate SQL_Latin1_General_CP850_Bin),
	            @param=RIGHT(@token, LEN(@token)-@endofname+1)
	          SELECT
	            @token=LEFT(@token, @endofname-1),
	            @Contents=RIGHT(' '+@contents, LEN(' '+@contents+'|')-@end-1)
	          SELECT  @name=stringvalue FROM @strings
	            WHERE string_id=@param --fetch the name
	        END
	      ELSE 
	        SELECT @Name=null,@SequenceNo=@SequenceNo+1 
	      SELECT
	        @end=CHARINDEX(',', @contents)-- a string-token, object-token, list-token, number,boolean, or null

            --20220308 add [A-Za-z0-9@+.e] -> [A-Za-z0-9@+-.e]
	      IF @end=0 
	        SELECT  @end=PATINDEX('%[A-Za-z0-9@+-.e][^A-Za-z0-9@+-.e]%', @Contents+' ' collate SQL_Latin1_General_CP850_Bin)
	          +1
	       SELECT
            @start=PATINDEX('%[^A-Za-z0-9@+-.e][A-Za-z0-9@+-.e]%', ' '+@contents collate SQL_Latin1_General_CP850_Bin)
	      --select @start,@end, LEN(@contents+'|'), @contents  
	      SELECT
	        @Value=RTRIM(SUBSTRING(@contents, @start, @End-@Start)),
	        @Contents=RIGHT(@contents+' ', LEN(@contents+'|')-@end)

	      IF SUBSTRING(@value, 1, 7)='@object' 
	        INSERT INTO @hierarchy
	          (NAME, SequenceNo, parent_ID, StringValue, [Object_ID], ValueType)
	          SELECT @name, @SequenceNo, @parent_ID, SUBSTRING(@value, 8, 5),
	            SUBSTRING(@value, 8, 5), 'object' 
	      ELSE 
	        IF SUBSTRING(@value, 1, 6)='@array' 
	          INSERT INTO @hierarchy
	            (NAME, SequenceNo, parent_ID, StringValue, [Object_ID], ValueType)
	            SELECT @name, @SequenceNo, @parent_ID, SUBSTRING(@value, 7, 5),
	              SUBSTRING(@value, 7, 5), 'array' 
	        ELSE 
	          IF SUBSTRING(@value, 1, 7)='@string' 
	            INSERT INTO @hierarchy
	              (NAME, SequenceNo, parent_ID, StringValue, ValueType)
	              SELECT @name, @SequenceNo, @parent_ID, stringvalue, 'string'
	              FROM @strings
	              WHERE string_id=SUBSTRING(@value, 8, 5)
	          ELSE 
	            IF @value IN ('true', 'false') 
	              INSERT INTO @hierarchy
	                (NAME, SequenceNo, parent_ID, StringValue, ValueType)
	                SELECT @name, @SequenceNo, @parent_ID, @value, 'boolean'
	            ELSE
	              IF @value='null' 
	                INSERT INTO @hierarchy
	                  (NAME, SequenceNo, parent_ID, StringValue, ValueType)
	                  SELECT @name, @SequenceNo, @parent_ID, @value, 'null'
	              ELSE
                  Begin
                        --20220308 [^0-9] -> [^0-9-]
	                    IF PATINDEX('%[^0-9-]%', @value collate SQL_Latin1_General_CP850_Bin)>0 
                        Begin
                            set @ValueType='real'

                            --
	                        IF PATINDEX('%[^0-9-.]%', @value collate SQL_Latin1_General_CP850_Bin)>0
                            begin
                                set @ValueType='real'
                            end
                            else if len(@value)>19
                            begin
                                set @ValueType='dec(26,12)'
                            end
                            else
                            begin
                                set @ValueType='dec(18,6)'
                            end


	                        INSERT INTO @hierarchy
	                        (NAME, SequenceNo, parent_ID, StringValue, ValueType)
	                        SELECT @name, @SequenceNo, @parent_ID, @value, @ValueType
                        End
	                    ELSE
                        Begin
                            --20220308
                            set @ValueType='int'
                        
                            if len(@value)>11
                            begin
                                set @ValueType='bigint'
                            end
                            else if -2147483648<=convert(bigint,@value) and convert(bigint,@value)<=2147483647
                            begin
                                set @ValueType='int'
                            end
                            else
                            begin
                                set @ValueType='bigint'
                            end

	                        INSERT INTO @hierarchy
	                        (NAME, SequenceNo, parent_ID, StringValue, ValueType)
	                        SELECT @name, @SequenceNo, @parent_ID, @value, @ValueType
                        End

                   End
	      if @Contents=' ' Select @SequenceNo=0
        END
    END

    INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, [Object_ID], ValueType)
    SELECT '-',1, NULL, '', @parent_id-1,isnull(@type,'Unknow') --20170316 add isnull
    --
    RETURN
END

GO
